Title: InfiniBand Scalability in Open MPI

Author(s):

Abstract:

Infiniband is becoming an important interconnect
technology in high performance computing. Recent efforts in large
scale Infiniband deployments are raising scalability questions in the
HPC community. Open MPI, a new open source implementation of the MPI
standard targeted for production computing, provides several
mechanisms to enhance Infiniband scalability. Initial comparisons with
MVAPICH, the most widely used Infiniband MPI implementation, show
similar performance but with much better scalability
characteristics. Specifically, small message latency is improved by up
to 10% in medium/large jobs and memory usage per host is reduced by
as much as 300%. In addition, Open MPI provides predictable latency
that is close to optimal without sacrificing bandwidth performance.